This invention relates to an electronic musical instrument capable of performing a tone control by an after-touch operation on an operator designating a tone pitch such as a key in a keyboard.
There are electronic musical instruments having a keyboard and being capable of performing a tone control by an after-touch, i.e., a key operation subsequent to an initial touch on a key.
For example, Japanese Patent Publication No. 21282/1973 concerning an invention entitled "Effect tone control device in an electronic musical instrument" discloses a technique according to which musical effects such as vibrato and tremolo are imparted to a tone by an after-touch operation, Japanese Utility Model Publication No. 43714/1979 concerning an invention entitled "Tone control device for an electronic musical instrument" discloses a technique according to which tone volume of one of two tone source signals is controlled by an after-touch operation and the two tone source signals are mixed together for propagation as a sound, and Japanese Utility Model Publication No. 16960/1985 concerning an invention entitled "Automatic rhythm performance device" discloses a technique according to which tempo, rhythm pattern, rhythm tone color etc. are changed by an after-touch operation.
In these prior art tone control devices using an after-touch operation, start of generation of a tone relies entirely on an initial touch on a key, and changing in tone volume and tone color and imparting of effects such as vibrato and tremolo by an after-touch operation are limited to the tone generated by the initial touch on the key. In the rhythm producing electronic musical instrument, what is realized by an after-touch operation is limited to change in a rhythm pattern.
It is an object of the invention to provide an electronic musical instrument capable of regenerating a tone relating to a depressed key by an after-touch operation and thereby capable of simulating a performance technique of a high degree in a natural musical instrument.